Drug eluting stent for the treatment of dialysis graft stenoses

Abstract

A drug-eluting stent having a first cell pattern at one end and a second cell pattern on an opposite end. The cells in the first cell pattern have a smaller MCUSA than those in the second cell pattern. An anti-restonic drug can be coated on the first cell pattern and an anti-thrombotic drug on the second, with the anti-thrombotic drug overlaying and covering both the first and second cell patterns. The stent is operatively positionable at a distal graft-vein anastomosis with the first cell pattern adjacent the stenosis, and with the second cell pattern positioned adjacent the vein or the graft.

1 - 33 . (canceled) 
     
     
         34 . A method, comprising:
 positioning a stent having a first stent portion adjacent one end thereof and a second stent portion adjacent an opposite end thereof at a stenosis at an anastamosis with the first stent portion adjacent the stenosis;   the first portion defining a first maximum circular uncovered surface area (MCUSA1); and   the second stent portion defining a second maximum circular uncovered surface area (MCUSA2);   wherein MCUSA1 is less than MCUSA2.   
     
     
         35 . The method of  claim 34 , wherein the positioning includes positioning the stent construction with the second stent portion adjacent the vein. 
     
     
         36 . The method of  claim 34 , wherein the positioning includes positioning the stent construction with the second stent portion adjacent a graft. 
     
     
         37 - 39 . (canceled) 
     
     
         40 . The method of  claim 34 , wherein the first stent portion has a drug eluting coating on at least the abluminal surfaces thereof. 
     
     
         41 . The method of  claim 34 , wherein the second stent portion has an anti-thrombotic coating on at least the luminal surfaces thereof. 
     
     
         42 . The method of  claim 34 , wherein the first stent portion has an anti-restenotic drug eluting coating on luminal and abluminal surfaces thereof. 
     
     
         43 . The method of  claim 34 , wherein the second stent portion has an anti-thrombotic coating on luminal and abluminal surfaces thereof. 
     
     
         44 . The method of  claim 34 , wherein the luminal and abluminal surfaces of the entire stent has an anti-thrombotic coating. 
     
     
         45 . The method of  claim 34 , wherein the positioning includes delivering the stent using a catheter via puncture of a proximal graft. 
     
     
         46 . The method of  claim 34 , wherein the positioning includes delivering the stent using a catheter via a central vein or artery. 
     
     
         47 . A stent, comprising:
 a stent having a first end and an opposite second end; and   the stent having a first stent zone extending from the first end along a length thereof proximate to the first end and spaced from the second end and a second stent zone extending from the second end along a length thereof proximate to the second end and spaced from the first end,   wherein each one of the cells in the first stent zone defines an open space that contains a first maximum circular uncovered surface area (MCUSA1) and each one of the cells in the second stem zone defines an open space that contains a second first maximum circular uncovered surface area (MCUSA2), wherein MCUSA1 is less than MCUSA2;   wherein the stent has a length measured as the distance between the first and second ends and the first stent zone occupies from 20% up to about 50% of the stent length and the second stent zone occupies the remaining 80% to about 50%, respectively.   
     
     
         48 . The stent of  claim 47 , wherein the first maximum circular area is two to five mm 2  and the second maximum circular area is six to eighty mm 2 . 
     
     
         49 . The stent of  claim 47 , wherein the first maximum circular area is approximately 3.5 mm 2  and the second maximum circular area is approximately 19 mm 2 . 
     
     
         50 . The stent of  claim 47 , wherein an anti-restenotic drug is on at least an abluminal surface of the first zone, and an anti-thrombotic drug is on at least a luminal surface of the second zone. 
     
     
         51 . The stent of  claim 47 , wherein the first zone has a length of one to three cm, the second zone has a length of two to six cm and the stent has a length of four to eight cm, or wherein the first zone has a length of approximately two cm, the second zone has a length of approximately four cm and the stent has a length of approximately six cm. 
     
     
         52 . A dialysis graft kit, comprising:
 a graft for being connected to a vessel; and   a stent for supporting the graft when the graft is connected to the vessel, the stent comprising:
 a first end and an opposite second end, 
 the stent having a first stent zone extending from the first end and spaced from the second end and a second stent zone extending from the second end and spaced from the first end. 
 wherein when the stent is expanded within the graft and supports the graft, each of the cells in the first stent zone define an open space that contains first maximum circular uncovered surface area (MCUSA1) and each of the cells in the second stent zone define an open space that contains a second maximum circular uncovered surface area (MCUSA2), wherein MCUSA1 is less than MCUSA2, 
 the first stent zone occupies about 33% of the stent length, 
 the second stent zone occupies about 66% of the stent length, and 
 a first drug or drug combination on the first zone but not on the second zone, and 
   a second drug or drug combination on the second zone but not the first zone.   
     
     
         53 . The dialysis graft kit of  claim 52 , further comprising:
 a third stent zone occupying a portion of the length of the stent not occupied by the first stent zone and the second stent zone,   wherein each of the cells in the third stent zone define an open space that contains a third maximum circular area smaller than the second maximum circular area and larger than the first maximum circular area.   
     
     
         54 . The stent of  claim 47 , further comprising:
 a third cell pattern of the stent located between the first and second cell patterns,   wherein each of the cells in the third cell pattern contain a third maximum circular area smaller than the second maximum circular area and larger than the first maximum circular area.   
     
     
         55 . The stent of  claim 47 , further comprising:
 a third cell pattern of the stent located between the first and second cell patterns,   wherein the third cell pattern has a maximum circular area that gradual increases for cells at the end adjacent the first cell pattern to the opposite end adjacent the second cell pattern.   
     
     
         56 . The stem of  claim 47 , wherein the first cell pattern occupies about 33% of the total stent length and the second cell pattern occupies about 66% of the total stent length.